Vacuum pump



Feb. 23, 1932. G. R. BRowN'ET AL VACUUM PUMP Filed Mayiso, 1930 20 2l /b 2l 20 l INVENTORS n/ye /'ayff @WM f/yf@ fw? y Patented Feb. 23, 1932 UNITED STATES GEORGE n. BROWN AND Queneau. NAB, or -cnEvE'LANn Vomc,lfAs'sI@Nous NORTH AMERICAN MANurAcTUnrNG coMPANsLbF :oLEvnLANn o1a1o,-A .j .con,-

PORATION OF OHIO VACUUM PUMP Application mea May aalieso. seriai N. 457,632.,

This invention relates to vacuum blowers of centrifugal type such as adapted for service in connection with `carrierrsystems and the like. Y

While the effect of blower operation in such service is to evacuate apart of the system so as to produce therein pressuresbelow that of the atmosphere, of course the blower itself acts merely as a pump to move air from the system into the atmosphere. lIn other words, the rotor of the blower operates as always, except that its inlet is at a pressure below atmospheric. Since the air discharged by the rotor has already served its purpose, its disposition is immaterial to the system, except where, as is often the case, the blower is so located indoors thatV draftsmust be avoided.

It is the object of our invention to provide simple yet efficient means for dissipating the rotorV discharge with minimum agitation of the surrounding atmosphere, and to this end it is a further object of the invention to so proportion the rotor itself and associated` partsA that the rotor` discharge velocity is minimized without reducing the eiciency of evacuation.l x v Y The exact nature of the invention together with further objects and advantages thereof will be apparent from the following description taken in connection with the accompanying drawings, in which Fig. 1 is a typical section on a diametral plane', of a blower constructed according to the principles of our invention; and Fig. 2'is a detail of the same in end elevation and at a smaller scale. Y

With reference now to the'dra-win'gs,1is

the rotor, mounted on Vthe shaft 2 carried-ink suitable bearings not shown, and arrangedto be driven by the usual electric motorv or equivalent means. The rotor may beymade up as indicated of a pair of spaced enddisks 3 each secured with a hub casting 4 which in turn is secured upon a bushing 5 made fast,

upon the shaft 2, bymeans'ofa nut `6.

Each of therotor disks 3 is dished inward! ly so that the space between the disks, longitudinally of the rotor,rincreases with the radial distance from the shaft, 2. In other words the so-called disks are actually cones.

Vsubstantially Vcal casing member 16 concentric with the Between the. disks 3 are arranged 'in circumferentially lspaced relation aVv number of ra'` dially extendingblades- 7. The'hub 4L has anv- "annularjopening SK-Opposite theend-ofthe'- i shaft 2, lwhich'serves asinlet mouth fort-he 55 i 'rotor'.f y

- lt'will: be apparent that theldescribed di'.

vcrgence of the' disks 3- toward the periphery ofthe rotor will `provide alower discharge velocity than would be thecase were the disks notdished as described. ,Y A f 4 A'casing is provided forv saidrrotor and maybe constructed as indicated having a pair `o'fca'stings 9,-10, serving as -basei portions.

The casting 9 is annular and carried bythe.

neck Q11A which ,as vwill be noticed has its through openingv 12 diverging toward the tween these parts as indicated to provide ya The casting 10 may be solid except fora cen-kr tralV clearance opening 13 for the shaft 2.

VSecured respectively with the castingsQ and uninterrupted passageway. 76

y mouth 8 of the rotor, the casting9 fitting bey 10 are a pair of casing members ltand l15 arranged one on either side, or more strictly on either .end of the rotor 1.v These casing members 14 and 15 extend radially beyond the circumferential.extremity of the rotor,v and at their peripheries are connected by acylindri- I rotor. The members 14 and`15 may be stiffn ened by annular members y22 of angular sec-V tion and withV flanges inwardly turned'immediately adjacent the rotor periphery. Thus an annular chamber. 17 is formed, extending 55, a about the peripheryof 'the rotor to re'ceive the *y ,y

discharge therefrom. Y y

The casing parts which form this chamber 17 are also formed to provide controlledl exit to the atmosphereV for air forced into the chamber by the rotor. j To this end the casing members 111- and 15 may be provided with 19 joined with` their casing members by theV` lcurved annular shoulders indicated' as at e provided y 20. Similar openings 21 may in the peripheral lcasingmember 16.I

It will be apparent that byV theY describedY openingsdischarge from the' chamber 17 will be quiet and with minimum agitation of the surrounding atmosphere, the casing provid-- ing an expansion` chamber adapted to operate with the effect of a muller. Whatwe claim is: l. In a vacuum blower of a rotor casing havinga''portion arranged peripherally of the rotor and perforated forv dissipating thev rotor discharge, and having at each perforation an outstanding neclpor- Y y tion supported by a curvedlshoulder portion,"

Y whereby discharge to the atmosphere willbe Y 15`Y` with minimum agitation.

- .-2.1n. a'ldevicelof the class described, a

blower rotorlhaving diverging side walls to' diminish` acceleration of flow therebetween, a housing about said rotor and having an outerperiph'eral wall portion and side wall portions but being open inwardly to provide an annular Vtrough-like receiver into which thev rotor may directly discharge, said housing having its side walls extending radially inwardly of said 4receiver to enclose' the side lwalls of the rotor, said reoeiver'havingzper- Vforations to allow discharge to the atmosl phere. Y Y Y ,In testimony whereof we hereby affix our signatures.

. Y GEORGE R.. BROWN.

GEORGE E. NAAB.

centrifugal type, 4 y 

